People like to communicate with each other; it is natural to share one's own thoughts, and it is entertaining and informative to learn from others. Individuals generally communicate most with their own closest real-world friends and colleagues, and sometimes with those friends and colleagues' own contacts. Individuals often also share other information with one other, such as digital photographs of children and events, gossip, practical tips, jokes, political opinion, etc.
The sharing of each of these types of information has been made easier in recent years due to the emergence of online social networks, which are online communities through which a registered user may form virtual relationships with other registered users (often only after both registered users agree) and then submit information that can be viewed by his/her respective acquaintances (and perhaps others). For example, a user can compose a social network post about his/her current activities or feelings, and that information may be displayed when that individual's social network contacts/friends access their own accounts on the social network. On some social networks, a user can “check in” at a venue (such as a bar or restaurant) to indicate to that user's social network contacts the presence of that user at the venue. Alternatively, a user may take a photograph with a smartphone and then post it to his/her social network profile. When social network contacts of the user log into the social network (such as by activating an application on a smartphone for reviewing content from the social network), they can often see such activity and/or content posted by their social network contacts, including the user.